In May 2021, our shareholders approved the Chubb Limited 2016 Long-Term Incentive Plan, as amended and restated (the Amended 2016 LTIP). Under the Amended 2016 LTIP, Common Shares of Chubb are authorized to be issued pursuant to awards, including stock options, stock appreciation rights, performance shares, performance units, restricted stock, and restricted stock units.

Chubb principally issues restricted stock grants and stock options on a graded vesting schedule, with equal percentages of the award subject to vesting over a number of years (typically three or four). Chubb recognizes compensation cost for vesting of restricted stock and stock option grants with only service conditions on a straight-line basis over the requisite service period for each separately vesting portion of the award as if the award were, in-substance, multiple awards. We incorporate an estimate of future forfeitures in determining compensation cost for both grants of restricted stock and stock options.

In addition, Chubb grants performance-based restricted stock to certain executives that vest based on certain performance criteria as compared to a defined group of peer companies. Performance-based stock awards comprise target awards and premium awards that cliff vest at the end of a 3-year performance period based on both Chubb tangible book value (Chubb shareholders' equity less goodwill and intangible assets attributable to Chubb, net of tax) per share growth and P&C combined ratio compared to our peer group. Premium awards are subject to an additional vesting provision based on total shareholder return (TSR) compared to our peer group. Shares representing target awards and premium awards are issued when the awards are approved and are subject to forfeiture if applicable performance criteria are not met at the end of the 3-year performance period.

Under the Amended 2016 LTIP, 32,900,000 Common Shares are authorized to be issued (which includes all shares available for delivery since the establishment of the Chubb Limited 2016 Long-Term Incentive Plan in 2016). This is in addition to any shares subject to awards outstanding under the ACE Limited 2004 Long-Term Incentive Plan (2004 LTIP) immediately prior to the effective date of the Amended 2016 LTIP that are forfeited, expired or canceled after such effective date without delivery of shares (or which result in forfeiture of shares back to Chubb). At December 31, 2023, a total of 12,533,303 shares remain available for future issuance under the Amended 2016 LTIP, which includes shares forfeited, expired or canceled relating to grants under the 2004 LTIP.

Unrecognized compensation expense related to the unvested portion of Chubb's employee share-based awards of restricted stock, restricted stock units, and stock options was $350 million at December 31, 2023 and is expected to be recognized over a weighted-average period of approximately 1.5 years.

Both incentive and non-qualified stock options are principally granted at an option price per share equal to the grant date fair value of Chubb's Common Shares. Stock options are generally granted with a 3-year vesting period and a 10-year term. Stock options vest in equal annual installments over the respective vesting period, which is also the requisite service period.

Chubb's 2023 share-based compensation expense includes a portion of the cost related to the 2020 through 2023 stock option grants. Stock option fair value was estimated on the grant date using the Black-Scholes option-pricing model that uses the weighted-average assumptions noted below:

The risk-free interest rate is based on the U.S. Treasury yield curve in effect at the time of grant. The expected life (estimated period of time from grant to exercise date) is estimated using the historical exercise behavior of employees. The expected volatility is calculated as a blend of (a) historical volatility based on daily closing prices over a period equal to the expected life assumption and (b) implied volatility derived from Chubb's publicly traded options.


(Intrinsic Value in millions of U.S. dollars)	Number of Options	Weighted-Average Exercise Price		Weighted-Average Fair Value		Total Intrinsic Value
Options outstanding, December 31, 2020	11,478,183	$	125.09
Granted	1,805,234	$	164.89	$	33.05
Exercised	(2,284,795)	$	112.12			$	140
Forfeited and expired	(236,135)	$	150.16
Options outstanding, December 31, 2021	10,762,487	$	133.94
Granted	1,731,904	$	198.36	$	35.46
Exercised	(1,878,147)	$	117.83			$	163
Forfeited and expired	(205,966)	$	171.45
Options outstanding, December 31, 2022	10,410,278	$	146.81
Granted	1,540,002	$	208.60	$	51.32
Exercised	(1,249,350)	$	127.45			$	107
Forfeited and expired	(220,046)	$	191.57
Options outstanding, December 31, 2023	10,480,884	$	157.24			$	721
Options exercisable, December 31, 2023	7,497,652	$	141.08			$	637

The weighted-average remaining contractual term was 5.6 years for stock options outstanding and 4.4 years for stock options exercisable at December 31, 2023. Cash received from the exercise of stock options for the year ended December 31, 2023 was $158 million.

Grants of restricted stock and restricted stock units awarded under the Amended 2016 LTIP typically have a 4-year vesting period, subject to vesting as to one-quarter of the award each anniversary of grant. Restricted stock and restricted stock units are principally granted at market close price on the day of grant. Each restricted stock unit represents our obligation to deliver to the holder one Common Share upon vesting.

The following table presents a roll-forward of our restricted stock awards. Included in the roll-forward below are 12,994 restricted stock awards, 13,440 restricted stock awards, and 15,586 restricted stock awards that were granted to non-management directors during the years ended December 31, 2023, 2022, and 2021, respectively:


	Service-based Restricted Stock Awards and Restricted Stock Units			Performance-based Restricted Stock Awards and Restricted Stock Units
	Number of Shares	Weighted-Average Grant-Date Fair Value		Number of Shares	Weighted-Average Grant-Date Fair Value
Unvested restricted stock, December 31, 2020	3,263,295	$	142.32	572,318	$	142.38
Granted	1,288,042	$	165.32	294,315	$	164.75
Vested	(1,283,185)	$	140.62	(169,442)	$	143.07
Forfeited	(216,341)	$	150.19	—	$	—
Unvested restricted stock, December 31, 2021	3,051,811	$	152.19	697,191	$	151.74
Granted	1,193,016	$	199.18	296,944	$	199.09
Vested	(1,191,452)	$	148.18	(199,343)	$	133.90
Forfeited	(199,505)	$	168.12	—	$	—
Unvested restricted stock, December 31, 2022	2,853,870	$	172.39	794,792	$	173.83
Granted	1,166,706	$	208.07	407,825	$	208.60
Vested	(1,142,911)	$	161.88	(203,533)	$	150.11
Forfeited	(203,850)	$	186.58	—	$	—
Unvested restricted stock, December 31, 2023	2,673,815	$	191.35	999,084	$	192.85

Prior to 2009, legacy ACE granted restricted stock units with a 1-year vesting period to non-management directors. Delivery of Common Shares on account of these restricted stock units to non-management directors is deferred until after the date of the non-management directors' termination from the Board. Legacy Chubb Corp historically allowed directors and certain key employees of Chubb Corp and its subsidiaries to defer a portion of their compensation earned with respect to services performed in the form of deferred stock units. In addition, legacy Chubb Corp provided supplemental retirement benefits for certain employees through its Defined Contribution Excess Benefit Plan in the form of deferred shares of stock. The minimum vesting period under these legacy Chubb Corp deferred plans was 1-year and the maximum was 3-years. Employees and directors had the option to elect to receive their awards at a future specified date or upon their termination of service with Chubb. At December 31, 2023, there were 100,965 deferred restricted stock units.

The ESPP gives participating employees the right to purchase Common Shares through payroll deductions during consecutive subscription periods at a purchase price of 85 percent of the fair value of a Common Share on the exercise date (Purchase Price). Annual purchases by participants are limited to the number of whole shares that can be purchased by an amount equal to ten percent of the participant's compensation or $25,000, whichever is less. The ESPP has two six-month subscription periods each year, the first of which runs between January 1 and June 30 and the second of which runs between July 1 and December 31. The amounts collected from participants during a subscription period are used on the exercise date to purchase full shares of Common Shares. An exercise date is generally the last trading day of a subscription period. The number of shares purchased is equal to the total amount, at the exercise date, collected from the participants through payroll deductions for that subscription period, divided by the Purchase Price, rounded down to the next full share. Participants may withdraw from an offering before the exercise date and obtain a refund of amounts withheld through payroll deductions. Pursuant to the provisions